Geomagnetic Storm Forecast

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3-Day Forecast - 2023 Jul 21 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Jul 21 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Jul 21-Jul 23 2023 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Jul 21-Jul 23 2023

             Jul 21       Jul 22       Jul 23
00-03UT       2.67         3.00         3.33     
03-06UT       3.33         2.33         3.00     
06-09UT       2.33         3.00         2.00     
09-12UT       2.00         2.00         1.67     
12-15UT       3.67         1.67         1.33     
15-18UT       4.67 (G1)    1.67         1.33     
18-21UT       3.67         3.33         1.33     
21-00UT       2.67         3.67         1.67     

Rationale: G1 (Minor) geomagnetic storm conditions are likely on 21 Jul
due to anticipated CME influences.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Jul 21-Jul 23 2023

              Jul 21  Jul 22  Jul 23
S1 or greater   25%     15%      5%

Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Jul 21-Jul 23 2023

              Jul 21        Jul 22        Jul 23
R1-R2           45%           45%           45%
R3 or greater    5%            5%            5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
over 21-23 Jul.
                        

3-Day Forecast - 2023 Jul 20 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Jul 20 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Jul 20-Jul 22 2023 is 5.33 (NOAA Scale
G1).

NOAA Kp index breakdown Jul 20-Jul 22 2023

             Jul 20       Jul 21       Jul 22
00-03UT       1.00         4.33         3.00     
03-06UT       1.33         4.67 (G1)    2.33     
06-09UT       0.67         3.67         3.00     
09-12UT       1.33         3.67         2.00     
12-15UT       3.33         3.00         2.33     
15-18UT       5.00 (G1)    2.33         2.33     
18-21UT       5.33 (G1)    2.67         3.33     
21-00UT       4.67 (G1)    2.67         2.67     

Rationale: G1 (Minor) or greater geomagnetic storms are likely on 20-21
Jul due to possible arrival of two CMEs from 17 and 18 Jul.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
above S-scale storm level thresholds.

Solar Radiation Storm Forecast for Jul 20-Jul 22 2023

              Jul 20  Jul 21  Jul 22
S1 or greater   85%     35%     10%

Rationale: S1 (Minor) or greater solar radiation storms are possible on
20-21 Jul as the 10 MeV flux is expected to remain elevated.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Jul 19 2023 1725 UTC.

Radio Blackout Forecast for Jul 20-Jul 22 2023

              Jul 20        Jul 21        Jul 22
R1-R2           50%           45%           45%
R3 or greater   15%           10%            5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
all three days and a slight chance for R3 (Strong) or greater blackouts
on 20-21 Jul.
                        

3-Day Forecast - 2023 Jul 19 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Jul 19 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Jul 19-Jul 21 2023 is 5.33 (NOAA Scale
G1).

NOAA Kp index breakdown Jul 19-Jul 21 2023

             Jul 19       Jul 20       Jul 21
00-03UT       1.33         2.00         4.33     
03-06UT       1.33         1.67         4.33     
06-09UT       1.33         2.00         3.67     
09-12UT       1.33         3.33         3.67     
12-15UT       1.67         4.33         3.33     
15-18UT       2.00         5.00 (G1)    2.33     
18-21UT       2.67         5.33 (G1)    3.00     
21-00UT       1.67         5.00 (G1)    2.67     

Rationale: G1 (Minor) geomagnetic storms are likely on 20 Jul due to
possible CME influences.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
above S-scale storm level thresholds.

Solar Radiation Storm Forecast for Jul 19-Jul 21 2023

              Jul 19  Jul 20  Jul 21
S1 or greater   99%     70%     50%

Rationale: As of this report, 10 MeV protons are continuing to steadily
decrease but an S1 (Minor) storm remains in progress. This activity was
associated with a long-duration M5 flare.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Jul 18 2023 2027 UTC.

Radio Blackout Forecast for Jul 19-Jul 21 2023

              Jul 19        Jul 20        Jul 21
R1-R2           55%           45%           45%
R3 or greater   20%           20%           15%

Rationale: Solar activity is likely to be moderate, with a likelihood of
M-class flares (R1-R2) and slight chance of an X-class (R3-Strong) event
19 Jul. A slight decrease to lower solar activity, with a chance of
M-class flares and continuing slight chance of X-class flares exists on
20-21 Jul. Primary contributors to this forecast are Regions 3372, 3373,
and
3376.
                        

3-Day Forecast - 2023 Jul 18 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Jul 18 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 5 (NOAA Scale
G1).
The greatest expected 3 hr Kp for Jul 18-Jul 20 2023 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Jul 18-Jul 20 2023

             Jul 18       Jul 19       Jul 20
00-03UT       4.67 (G1)    2.00         2.33     
03-06UT       3.00         1.67         2.67     
06-09UT       2.33         2.67         2.33     
09-12UT       2.00         2.67         2.33     
12-15UT       2.00         2.33         2.00     
15-18UT       3.33         3.00         2.33     
18-21UT       2.33         3.67         2.33     
21-00UT       4.67 (G1)    2.67         2.67     

Rationale: Isolated periods of G1 (Minor) storm levels expected on 18
Jul due to continuing disturbances and possible arrival of a close
proximity or glancing blow CME from 15 Jul. 

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
above S-scale storm level thresholds.

Solar Radiation Storm Forecast for Jul 18-Jul 20 2023

              Jul 18  Jul 19  Jul 20
S1 or greater   99%     65%     20%

Rationale: S1 (Minor) or greater solar radiation storms are expected on
18 Jul due to the M5 flare from Region 3363. Proton levels are expected
to decrease steadily through 19-20 Jul.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R2 levels were observed over the past 24
hours. The largest was at Jul 18 2023 0006 UTC.

Radio Blackout Forecast for Jul 18-Jul 20 2023

              Jul 18        Jul 19        Jul 20
R1-R2           50%           50%           45%
R3 or greater   20%           20%           15%

Rationale: There is a chance of M-class flares (R1-R2; Minor-Moderate)
and a slight chance of X-class (R3; Strong) events due to the latest
decreased flare and activity trends, along with the departure of Region
3363 over the next 1-2 days.
                        

3-Day Forecast - 2023 Jul 17 1230 UTC

:Product: 3-Day Forecast
:Issued: 2023 Jul 17 1230 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 5 (NOAA Scale
G1).
The greatest expected 3 hr Kp for Jul 17-Jul 19 2023 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Jul 17-Jul 19 2023

             Jul 17       Jul 18       Jul 19
00-03UT       3.00         4.67 (G1)    2.00     
03-06UT       2.00         4.67 (G1)    1.67     
06-09UT       4.33         4.67 (G1)    2.67     
09-12UT       4.33         4.33         2.67     
12-15UT       2.67         4.00         2.33     
15-18UT       3.67         3.00         3.00     
18-21UT       4.33         2.00         3.67     
21-00UT       4.67 (G1)    2.33         2.67     

Rationale: Continuing CME influences are expected to result in unsettled
to G1 (Minor) levels on 17-18 Jul with a chance for G2 (Moderate).

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Jul 17-Jul 19 2023

              Jul 17  Jul 18  Jul 19
S1 or greater   25%     20%     10%

Rationale: The greater than 10 MeV proton flux is expected to remain
mildly enhanced, with a chance of S1 levels on 17 Jul due primarily to
the recent activity escalation in Region 3363 and its favorable
location. Proton flux is expected to continue at background on 18-19
Jul, with a slight chance of a S1 storm as Region 3363 begins to rotate
to and beyond the west limb.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Jul 16 2023 1746 UTC.

Radio Blackout Forecast for Jul 17-Jul 19 2023

              Jul 17        Jul 18        Jul 19
R1-R2           60%           60%           50%
R3 or greater   25%           25%           15%

Rationale: The combined flare probabilities of mainly Regions 3363,
3372, and 3373 have led to a forecast of solar activity likely being
moderate - with C-class X-ray flux expected to continue as background
levels and a likelihood of M-class flares (R1-R2; Minor-Moderate) with a
chance of an X-class (R3; Strong) event on 17-18 Jul. Solar activity is
expected to be low, with a chance of M-class flares and slight chance of
X-class flares on 19 Jul.
                        

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